Simulink and arduino connection using instrumentation control toolbox

Hello, I am trying to send data from simulink to matlab using instrumentation toolbox. I have a 'constant block' connected to a 'to instrument block '. I want to turn a couple of lights on and off. (In reality i want to do something more complex but i need arduino to receive numbers from simulink(0-180)) As of now the arduino receives a signal but the arduino is not able to understand the received signal(I know this cause the receive light turns on when i run the simulation). The arduino code i am using is shown below

/************************* Private Variables(serial reading)*****************/ unsigned long loopTime, currentTime; const int serStrLen = 30; char serInStr[ serStrLen ]; // array that will hold the serial input string /*************************************************************/ const int ledPin = 13; const int ledPin2 = 12;

int ch; // Values to send on channels (duration of pulse minus start, in microseconds)

void setup() {

 pinMode(ledPin, OUTPUT); 
  pinMode(ledPin2, OUTPUT); // Set servo pin as an output pin
  Serial.begin(9600);         // connect to the serial port
  Serial.flush();
}

void loop() {

     if( readSerialString() ) 
     {
     Serial.println(serInStr); 
     }

    ch = abs(atoi( serInStr )); 

    if (ch==5 )
    {digitalWrite(ledPin,HIGH);
     digitalWrite(ledPin2, LOW);}
   else
    {digitalWrite(ledPin2, HIGH);
     digitalWrite(ledPin, LOW);}

}

/************* Serial Reading ************************************/

uint8_t readSerialString() { if(!Serial.available()) { return 0; } delay(10); // wait a little for serial data

memset( serInStr, 0, sizeof(serInStr) ); // set it all to zero
int i = 0;
while(Serial.available() && i<serStrLen ) {
  serInStr[i] = Serial.read();   // FIXME: doesn't check buffer overrun
  i++;
}
return i;  // return number of chars read
}

The know the above code works because when I send numbers via serial monitor, it works how it is supposed to.But when i try to send number 5 via simulink, the arduino does no respond the same way.

I am guessing i have to set a particular datatype in the 'to instrument' box or the ascii format string section in the 'to instrument' box settings.

Pls Help, any help would be appreciated.

[Shacks]

Update:: I noticed, the simulink model kind of works, I am unable to send 2 or three digit number, The arduino responds as if i am sending 2 or 3 separate single digit number. So now the question is , how do i send 2 or 3 digit numbers to arduino ?

[Josephine Gotz]

Hey, did you manage to solve this? I think maybe I have a similar problem. Thanks

Answer 1

[Jeremy]

hi Shacks, I have a quick question for you: how did you configure your 'to instrument'? i.e. under 'hardware configuration'I am wondering if that is my problem. I am not having any luck getting the simplest toy model, a constant-connected-to-a'to instrument' model to build. I get a generic 'errors encountered while building' error.

Answer 2

[Shacks]

I feel like i am talking to myself, anyways future reader(s) i solved it, just type in '%i\n' in ascii string format setting.

Answer 3

[Shacks]

Under output format, i selected ASCII Under format string '%i\n' Time out : 10 Buffer Size :8192 Interface: Serial Port: Select the right one Baudrate:9600

obviously the hardware setting should match to that of arduino. Under instrument initialization I made no changes.

Hope this helps.